Choi Yoo-jung

Choi is set to star in the web drama Cast: Age of Insiders in 2020.

Choi was part of My Mad Beauty 3 alongside Park Na-rae, Mijoo and Han Hye-jin. She was also part of the variety show The Gashinas. In September 2019, Choi participated in the survival program show, V-1, to select the Vocal Queen among the various girl group members, where only the top twelve girl group members in votes would progress and perform on the show. However, she was eliminated in the first episode, after losing out to bandmate Suyeon.

On May 2, 2018, Starship Entertainment and Fantagio revealed their plans to form a special four-member unit with members of their respective girl groups Cosmic Girls and Weki Meki, which they eventually revealed will be called WJMK. Weki Meki's Choi and Kim and Cosmic Girls' Seola and Luda released the single "Strong" on June 1, 2018, along with its accompanying music video. On August 8, she joined the JTBC reality program Secret Unnie with EXID's Hani.

After I.O.I parted ways on January 29, 2017 and ended their contract with YMC Entertainment, Choi and Kim Do-yeon filmed a reality show in the United States titled Dodaeng's Diary in LA which aired on TVING. Months later, Fantagio announced their plans to debut a new girl group, which they later revealed would be called Weki Meki. Both Choi and Kim made their official debut with the group on August 8, 2017 with the release of the single "I Don't Like Your Girlfriend" and the six-track EP Weme which had some of its lyrics written by Choi.

In January 2016, Choi joined Produce 101 along with Kim Do-yeon and three other Fantagio trainees with the hopes of debuting in an eleven-member girl group which would promote for a year under YMC Entertainment. Choi initially gained popularity for being chosen by vote as the center for the show's theme song "Pick Me", which had its music video premiere a month before the first show aired on the December 17, 2015 episode of M Countdown. Both Choi and Kim rose to high ranks during the program and eventually placed 3rd and 8th respectively in the show's finale on April 1, 2016, which allowed them to debut as members of I.O.I. On May 4, 2016, I.O.I released their debut single "Dream Girls" which had its rap parts penned by Choi and Im Na-young. Both members also wrote the lyrics for the EP's intro track "I.O.I". The group also promoted as a seven-member unit which Choi was also a part of with Kim, releasing the single "Whatta Man" on August 9, 2016. As part of I.O.I, Choi also released an OST with the unit and also collaborated with fellow members Chungha, Jeon Somi and fellow Produce 101 contestant Ki Hui-hyeon for the digital single "Flower, Wind and You". The song charted at number 42 on the Gaon Digital Chart. She also appeared in the music video of her label-mate ASTRO's song "Breathless" which was released on July 1, 2016. In November 2016, Choi joined the cast of Mnet's music variety show Golden Tambourine. She then released the single "Rise and Fall" together with Yoo Se-yoon, Shim Hyung-tak and Jo Kwon as part of the show's official soundtrack.

Choi Yoo-jung (Korean: 최유정 ; born November 12, 1999), better known by the mononym Yoojung, is a South Korean singer and songwriter signed under Fantagio. She debuted as member of I.O.I in May 2016 after achieving third place in the 2016 survival program Produce 101. In January 2017, I.O.I officially disbanded after eleven months of promotion. Following disbandment, she returned to her respective agency and eventually debuted with Weki Meki in August 2017.

Choi Yoo-jung was born in Guri, Gyeonggi Province, South Korea on November 12, 1999. When she was younger, she wanted to become either a teacher or police officer but started to take an interest in performing. She joined Fantagio and trained for four years and seven months under the company before joining Mnet's girl group survival show Produce 101 in 2016 wherein she ended up debuting as a member of I.O.I. She attended Guri Girls' High School but eventually transferred to School of Performing Arts Seoul along with fellow I.O.I and Weki Meki member Kim Do-yeon after debuting due to their promotional activities.